The range of mutations that can drive cancer growth could be much wider than thought. An international research effort called the Cancer Genome Project has identified around 120 new genes that contain mutations promoting the disease.

"This is a lot more cancer genes than we expected to find," says Michael Stratton of the Wellcome Trust's Sanger Institute in Cambridge, UK, one of the leaders of the research.

The discovery of a single gene that contributes to cancer used to constitute a big step forward. Not any more. Declining costs for DNA sequencing make possible much bigger searches for cancer promoting mutations.

Scientists at the Wellcome Trust Sanger Institute, where one-third of the human genome was sequenced, have now pioneered decoding the sequence of cancer genomes. They have carried out the broadest survey yet of the human genome in cancer by sequencing more than 250 million letters of DNA code, covering more than 500 genes and 200 cancers.

The continued decline in the cost of DNA sequencing will eventually make the discovery of important mutations (whether harmful or beneficial) incredibly easy. Scientific instrumentation advances are more important than any one biomedical research discovery because the instrumentation advances make the discoveries possible.